The Assessment of Progeny Tests of Dairy Bulls made under Farm Conditions

1954 ◽  
Vol 1954 ◽  
pp. 75-82 ◽  
Author(s):  
A. T. G. McArthur

The main object of the artificial insemination service is herd improvement. This is facilitated by the larger selection differential obtained when only a small number of bulls are used. Robertson and Rendel (1954) have shown that artificially bred daughters by bulls used at centres outwith the Milk Marketing Board system did not outyield naturally bred daughters milking in the same herds and these results have been substantiated by data from the Board’s centres. This failure to select bulls better than those used in the average herd has probably been due to the multiple aims of selection necessary to satisfy all those interested in the artificial breeding movement and to the methods which have been used to evaluate bulls. A method has been designed aimed at improving this evaluation.

1956 ◽  
Vol 47 (4) ◽  
pp. 367-375 ◽  
Author(s):  
I. L. Mason ◽  
Alan Robertson

1. An analysis has been made of milk records from 13,000 cows bred by artificial insemination in Denmark.2. The herds were divided into three equal groups on the basis of their average production. The variance of yield within herds increased as the average yield increased, but the coefficient of variation declined slightly. The genetic variance was more than five times as large in the high-yielding herds than in the low, and correspondingly the heritabilities in low, medium and high herds were 0·05, 0·15 and 0·22 respectively. These were estimated from the variation observed between progeny groups of the same 152 bulls at each production level.3. No evidence was obtained of any sire-herd interaction for yield, either within or between management levels. The true ranking of bulls for breeding value was apparently the same at all levels.4. The heritability of fat content in the three groups was 0·27, 0·47 and 0·49 respectively, and no evidence of sire-herd interaction was found.5. The contemporary comparison method of assessing A.I. bulls for yield was found to have the accuracy expected in theory.6. These results are discussed in relation to those of other workers with which there are some discrepancies. On our results, a policy of choosing bulls on the basis of their daughters' performance in high-yielding herds should be the most satisfactory way of progeny-testing bulls used in artificial insemination.


1953 ◽  
Vol 36 (3) ◽  
pp. 199-204 ◽  
Author(s):  
Cecil Branton ◽  
T.E. Patrick ◽  
M.H. Newsom ◽  
G. D’Arensbourg

2010 ◽  
Vol 22 (1) ◽  
pp. 337
Author(s):  
J. L. Anema ◽  
J. K. Graham ◽  
R. W. Lenz ◽  
G. E. Seidel

The objective of this study was to optimize bovine sperm storage for up to 20 h between semen collection and sex sorting followedby cryopreservation. Two successive ejaculates were obtained from mature dairy bulls (Holstein, n = 5; Jersey, n = 3) via artificial vagina. Treatments were then applied to the neat semen to which antibiotics were added as recommended by Certified Semen Services (Columbia, MO). Nothing further was added to the control samples until staining with Hoechst 33342 for sorting. For Treatment 1, semen was diluted 9:1 with a MOPS solution resulting in 24 mM MOPS and similarly, Treatment 2 resulted in 24 mM MOPS +2% egg yolk. A subsample of each treatment and control was sorted by flow cytometry shortly after collection, and sperm then were frozen following standard processing procedures. The other subsample was stored at 15-18°C and sorted 20 h after collection followed by cryopreservation. pH measurements were made before staining samples for sorting. Samples were evaluated post-thaw for subjective progressive and total sperm motility, by computer-assisted sperm analysis (CASA, Berkeley, CA, USA), and by flow cytometry for sperm viability using propidium iodide and SYBR-14. Treatment 1 performed better than the control (Table 1), while results for Treatment 2 were similar to the control. Second ejaculates were superior to first ejaculates. pH measurements showed that addition of MOPS kept the pH about 0.2 units higher than the control, but pH declined similarly over time in all groups. While responses for the 20 h sort were numerically lower than the 0 h sort (P > 0.1), the majority of responses were acceptable for most, but not all bulls. In conclusion, storing sperm in 24 mM MOPS was beneficial. Surprisingly, 2% egg yolk negated the beneficial effect of MOPS, possibly due to increasing osmolarity by ∼15mOsM/kg due to pH adjustment. Addition of MOPS provided better results than the control for both the 0 h and 20 h sorts. Table 1.Main effect means of semen characteristics


1978 ◽  
Vol 91 (3) ◽  
pp. 579-585 ◽  
Author(s):  
A. J. Stark ◽  
G. J. Rowlands ◽  
R. Manston ◽  
A. E. McClintock

SummaryBlood samples were taken from 172 Friesian bulls during 1973–5 on three or four occasions. The bulls were in Milk Marketing Board cattle breeding centres in England and Wales and were from 1 to 14 years of age.The blood samples were analysed for packed cell volume, haemoglobin, erythrocytes, mean corpuscular volume and glucose, and samples of serum for the concentrations of albumin, total protein, urea-nitrogen, inorganic phosphate, Ca, Mg, K, Na and Cu.Packed cell volumes and haemoglobin and K concentrations were higher in bulls than those previously recorded in dairy cows. There were significant age relationships for packed cell volume, haemoglobin, albumin and globulin (P < 0·001), inorganic phosphate and erythrocytes (P < 0·01) and Ca and Mg (P < 0·05).Repeatability estimates were calculated and compared with estimates previously obtained for dairy cows.On the basis of improved contemporary comparisons of the bulls, there was a significant relationship between the average milk yield of a bulls daughters and the concentrations of urea, inorganic phosphate and K (P < 0·05) in the blood serum of the bull.


2020 ◽  
Vol 76 (06) ◽  
pp. 6411-2020
Author(s):  
JAROSŁAW SOBOLEWSKI

Artificial breeding technology has been an important subject of research from the very beginning of medicine and veterinary sciences. Several main directions should be distinguished within these methods: artificial insemination (including cryogenic semen preservation technology), transplantation (embryo transfer) and embryo culture in vitro. The first experiments in this field date back to the late 18th century, when Lazarro Spallanzani performed such experiments on animals. The late 19th and the early 20th centuries saw the development of artificial insemination, which became a routine procedure, significantly facilitating breeding. The first successful experiments in embryo transplantation were also carried out in 1890. The high potential of this method was recognized related to the intensification of breeding for specific individual traits without limitations imposed by breeding physiology. These procedures were limited for a long time to scientific experiments and were not introduced into medical practice until the early 1970s. Embryo culture in vitro was a separate problem and an even greater challenge for researchers. Significant experimental research in this field started only in 1949 and has been continued ever since. In the 1990s, the biotechnology of in vitro embryo culture was improved to the point of becoming one of the most promising fields of veterinary and zootechnical sciences.


Author(s):  
H J Bellamy ◽  
G J T Swanson

Following the introduction of the linear assessment method of evaluating conformation within the Dairy Progeny Testing Scheme run by the Artificial Insemination Organisation (now Genus) of the Milk Marketing Board in 1983 three new traits were included in 1985 and 1986. The new traits were Temperament, Ease of Milking and Fore Udder Angle. In addition information was collected on the number of hours since milked when the classification was carried out.The objective of this study was to establish whether the variation in linear scores was significantly affected by the number of hours since milked and also to estimate the phenotypic and genetic parameters for the new trails, in particular Temperament and Ease of Milking.


2011 ◽  
Vol 23 (1) ◽  
pp. 182
Author(s):  
H. Yong ◽  
B.-S. Bae ◽  
S.-D. Kim ◽  
S.-H. Hyun

In December 2009, 8 female Himalayan tahrs (Hemitragus jemlahicus) were synchronized by inserting CIDR devices for 13 or 15 days. One day before removal of the CIDRs, a combination of pregnant mare serum gonadotropin (PMSG) 400 IU and hCG 200 IU (PG600®, Intervet, Boxmeer, the Netherlands) was intramuscularly injected into each animal and PGF2α was injected at the time of CIDR withdrawal. Semen was collected by electrical stimulation, diluted, cooled to 5°C for 2 h, and maintained in a refrigerator before performing AI twice. Pregnancy diagnosis was conducted by Doppler ultrasonography on March 2, 2010. Four female Himalayan tahrs were impregnated, showing a fetus present in their uteri. In the first experiment in which CIDRs were inserted into the vagina of 4 Himalayan tahrs for 13 days, 3 of the tahrs were transcervically inseminated with fresh semen, whereas 1 was inseminated with frozen–thawed semen 33 h after CIDR removal. As a second insemination experiment, 46 h after CIDR removal, all 4 tahrs were inseminated with diluted (1:3) fresh semen. While the tahr that was later inseminated with frozen–thawed semen did not become pregnant, the other 3 Himalayan tahrs became pregnant. In the second experiment, CIDR devices were inserted into the vaginas of 4 Himalayan tahrs for 15 days. Extended (1:7)-chilled semen was used for transcervical insemination 42 and 49 h after CIDR withdrawal. When performing the second insemination, it was difficult or impossible to penetrate cervical canals. Thus, only 1 tahr became pregnant. These findings show 13 days of CIDR insertion, the dose of PMSG 400 IU and hCG 200 IU, and the use of PGF2α as beneficial for inducing oestrus synchronization, and prove that extended-chilled semen may also be used for artificial breeding of Himalayan tahrs. This is the first report of successful pregnancy induced by artificial insemination of fresh or extended-chilled semen in oestrus-synchronized Himalayan tahrs.


1956 ◽  
Vol 1956 ◽  
pp. 43-50 ◽  
Author(s):  
Alan Robertson ◽  
A. Stewart ◽  
E. D. Ashton

In the Proceedings of this Society two years ago, A. T. G. Macarthur (1954) presented a method for the evaluation of dairy sires under farm conditions. Since that time, considerable use has been made of this technique in the Bureau of Records of the Milk Marketing Board and in this paper we propose to discuss the method critically, in the light of the results obtained on over 1,500 bulls.As the experience we have gained has considerable bearing on the validity of this method, it would perhaps be valuable at the beginning to view the general problem of testing dairy bulls under British conditions. What evidence have we that the use of contemporary comparisons is the best tool that we have available for the assessment of dairy bulls? We must bear in mind here that we have two distinct problems. The first is the assessment of bulls used in A.I. whose daughters have been bred and milked in many herds. The second is the assessment of bulls used in natural service.


Sign in / Sign up

Export Citation Format

Share Document